(1) Field of the Invention
The present invention relates generally to electronic components used in circuit board assemblies. This invention more particularly relates to electrical connectors used to establish an electrical connection between the electronic components and the mating component (e.g., circuit board) wiring.
(2) Background Information
The electronics industry is continually decreasing the size of electronic components while increasing the pin count thereof in an effort to increase the density of electronic packaging. As a result, the conventional practice for coupling leads to electronic components for use in circuit boards has gradually transitioned from through-hole technology to surface mount technology.
In through-hole technology the leads are deployed to protrude from the top and/or bottom major surfaces of the package with the leads being oriented in a direction substantially normal to the plane thereof (i.e., normal to the plane of the mating component). These leads are then inserted through corresponding holes in the mating component for mechanical and electrical attachment by soldering.
In surface mount technology the leads are typically deployed about the periphery of the electronic component in a plane substantially parallel to the package, with the distal portions thereof offset from the plane of the package. The distal portions of the leads are then positioned on corresponding pads on the mating components for soldering. Surface mount technology tends to allow for closer spacing of the leads in X and Y directions (e.g., in the plane of a circuit board), a reduction in size of the overall package, and the placement of electronic components on both sides of a mating component.
For proper mounting on a circuit board it is typically necessary that the leads of surface mountable electronic components be correctly positioned and that the engagement surfaces (i.e., the distal ends) thereof lie in a substantially common plane, a property known in the art as lead coplanarity. However, in practice, in part owing to the increasingly tight tolerances, a significant percentage of electronic components fail to meet coplanarity requirements. For example, a defective or noncoplanar lead may exhibit a property known in the art as lead standoff, a defect characterized by a lead that sits too high above the mating component for a reliable solder connection to be made between the lead and a corresponding copper pad thereon. Defective leads may also be bent sideways, out, in or down moving the end of the pin from a plane common with the ends of the other pins.
Further, as the pin count increases and lead spacing decreases, other mechanical parameters of the component leads, such as lead pitch, missing leads, lead deformation and the like, also tend to be important for ensuring proper electrical interconnections when the electronic components are mounted on a mating component.
Therefore, there exists a need for improved electronic components and in particular a method for fabricating electrical connectors therefor that may be suitable for next generation technology.